Effect of X-ray Irradiation on Articular Cartilage Mechanical Properties

A load bearing tissue found at the ends of articulating bones, the articular cartilage provides low friction surfaces for efficient movement. Its mechanical properties are determined by the structure and composition of type II collagen, proteoglycans and interstitial fluid. This work investigates the effects of X-ray irradiation, previously shown to affect the biological properties of the articular tissue, on mechanical properties of articular cartilage using polarized light microscope for imaging and compressive modulus test applied to articular cartilage to determine the effects of the ionizing radiation on mechanical properties. According to the test results, the relaxation time is significantly longer in control than X-ray exposed samples, while the force is much higher showing that the X-ray irradiation causes the reduction in the stiffness of articular cartilage.